IERROR(III)                 10/29/73                  IERROR(III)







NAME

     ierror - catch Fortran errors



SYNOPSIS

     if ( ierror ( errno ) .ne. 0 ) goto label



DESCRIPTION

     Ierror provides a way of detecting errors during the running

     of  a  Fortran  program.   Its  argument is a run-time error

     number such as enumerated in fc (I).



     When ierror is called, it returns a 0 value; thus  the  goto

     statement  in  the  synopsis  is not executed.  However, the

     routine stores inside itself the call point  and  invocation

     level.   If and when the indicated error occurs, a return is

     simulated from ierror with a non-zero value; thus  the  goto

     (or  other statement) is executed.  It is a ghastly error to

     call ierror from a subroutine  which  has  already  returned

     when the error occurs.



     This routine is essentially tailored to catching end-of-file

     situations.  Typically it is called just before the start of

     the loop which reads the input file, and the goto jumps to a

     graceful termination of the program.



     There is a limit of 5  on  the  number  of  different  error

     numbers which can be caught.



SEE ALSO

     fc (I)



BUGS

     There is no way to ignore errors.